[2] TANABE SEIYAKU CO LTD,ANALYT RES LAB,YODOGAWA KU,OSAKA 532,JAPAN
来源:
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 1
|
1997年
/
04期
关键词:
D O I:
10.1039/a601900e
中图分类号:
O62 [有机化学];
学科分类号:
070303 ;
081704 ;
摘要:
Photochemical reaction of bicyclo[2.2.2[oct-5-en-2-ones has been investigated as a prelude to focused application to the synthesis of sesquiterpenes such as sesquicarene and sirenin. Diels-Alder reaction of cyclohexa-2,4-dienes, having different substituents (methylthiomethyl and methoxy) at the C-6 position, with a dienophile proceeds regio- and stereo-selectively to give bicyclo[2.2.2]oct-5-en-2-ones; their photolysis in benzene upon high-pressure Hg lamp irradiation affords decarbonylation products, bicyclo[4.1.0]hept-2-enes (trinorcarenes), stereoselectively. Replacement of the methylthiomethyl group with a 2-ethoxycarbonylvinyl group improves the sequential reaction.